drbd: debugfs: add callback_history
Add a per-connection worker thread callback_history
with timing details, call site and callback function.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index b908e9b..50776b3 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1905,6 +1905,29 @@
return 0;
}
+/* only called from drbd_worker thread, no locking */
+void __update_timing_details(
+ struct drbd_thread_timing_details *tdp,
+ unsigned int *cb_nr,
+ void *cb,
+ const char *fn, const unsigned int line)
+{
+ unsigned int i = *cb_nr % DRBD_THREAD_DETAILS_HIST;
+ struct drbd_thread_timing_details *td = tdp + i;
+
+ td->start_jif = jiffies;
+ td->cb_addr = cb;
+ td->caller_fn = fn;
+ td->line = line;
+ td->cb_nr = *cb_nr;
+
+ i = (i+1) % DRBD_THREAD_DETAILS_HIST;
+ td = tdp + i;
+ memset(td, 0, sizeof(*td));
+
+ ++(*cb_nr);
+}
+
#define WORK_PENDING(work_bit, todo) (todo & (1UL << work_bit))
static void do_device_work(struct drbd_device *device, const unsigned long todo)
{
@@ -2076,11 +2099,15 @@
while (get_t_state(thi) == RUNNING) {
drbd_thread_current_set_cpu(thi);
- if (list_empty(&work_list))
+ if (list_empty(&work_list)) {
+ update_worker_timing_details(connection, wait_for_work);
wait_for_work(connection, &work_list);
+ }
- if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags))
+ if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) {
+ update_worker_timing_details(connection, do_unqueued_work);
do_unqueued_work(connection);
+ }
if (signal_pending(current)) {
flush_signals(current);
@@ -2097,6 +2124,7 @@
while (!list_empty(&work_list)) {
w = list_first_entry(&work_list, struct drbd_work, list);
list_del_init(&w->list);
+ update_worker_timing_details(connection, w->cb);
if (w->cb(w, connection->cstate < C_WF_REPORT_PARAMS) == 0)
continue;
if (connection->cstate >= C_WF_REPORT_PARAMS)
@@ -2105,11 +2133,14 @@
}
do {
- if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags))
+ if (test_and_clear_bit(DEVICE_WORK_PENDING, &connection->flags)) {
+ update_worker_timing_details(connection, do_unqueued_work);
do_unqueued_work(connection);
+ }
while (!list_empty(&work_list)) {
w = list_first_entry(&work_list, struct drbd_work, list);
list_del_init(&w->list);
+ update_worker_timing_details(connection, w->cb);
w->cb(w, 1);
}
dequeue_work_batch(&connection->sender_work, &work_list);
